Page Write Cycle
(Address Controlled, ZZ = VIH)
t WC
A0~ A3
t MRC
t PC
t PC
t PC
t PC
t PC
t PC
t PC
A4~ A20
PCS1
PUB, PLB
WE
tAS (3)
Data In
Data Out
High-Z
t WHZ
Data Undefined
tDW tDH tDW tDH tDW tDH tDW tDH tDW tDH tDW tDH tDW tDH tDW tDH
Data Valid Data Valid Data Valid Data Valid Data Valid Data Valid Data Valid Data Valid
High-Z
t OW
Notes:
1. A write occurs during the overlap (tWP) of low PCS1 and PWE. A write begins when PCS1 goes low and PWE goes low with
asserting PUB or PLB for single byte operation or simultaneously asserting PUB and PLB for double byte operation. A write
ends at the earliest transition when PCS1 goes high and PWE goes high. The tWP is measured from the beginning of write to
the end of write.
2. tCW is measured from the PCS1 going low to end of write.
3. tAS is measured from the address valid to the beginning of write.
4. tWR is measured from the end of write to the address change. tWR applied in case a write ends as PCS1 or PWE going high.
5. Do not access device with cycle timing shorter than tRC (tWC) for continuous periods > 20 µs.
32 AT52BC3221A(T)
3466A–STKD–11/04